1. Technical Field
The subject matter relates to an apparatus for water treatment. The subject matter may relate to an apparatus for stormwater runoff treatment.
2. Description of Related Art
The following background information may present examples of specific aspects of the prior art (e.g., without limitation, approaches, facts, or common wisdom) that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon.
Generally, as of 2015, 772 communities in the United States have combined sewer systems, serving about 40 million people in cities through the United States of America. In these cities, stormwater and sanitary sewers are combined, rather than separated. The Environmental Protection Agency (EPA) Clean Water Act established in 1948 and amended in 1972, regulates surface discharge of waters into the streams and rivers. Overflows of raw sewage and inadequately controlled stormwater discharges from municipal sewer systems known as Combined Sewer Overflows (CSO's) and Storm Sewer Overflows (SSO's) has created a complex and costly challenge to these cities in reducing combined sewer overflows and sanitary sewer overflows that occur under relatively small rainfall events. These overflows are considered one of the major contributors to pollution of water systems. Typically, many of the Combined Sewer Overflows (CSO) and Storm Sewer Overflows (SSO) locations can be in flood plain areas, which have been modified since the early to mid-1800's during the Industrial Revolution for the purposes of establishing a railroad infrastructure and waterway infrastructure for moving goods during times of war and peace. Because of this history and the complexity of the combined sewer system, many cities may not afford to meet the EPA's Clean Water Act requirements due to the magnitude of costs that a gray (engineered) solution would require. Many cities are looking to Green stormwater infrastructure as a means to assist in reducing costs and improving water quality to meet the EPA's requirements. In many of these urban areas, however, open green space and the willingness of the private sector to utilize valuable land for this use is equally problematic.
Green stormwater infrastructure techniques, such as bioretention, evapotranspiration, and natural underground storage are currently in practice. These techniques have become Best Management Practices (BMP) for many state environmental protection and natural resource agencies. Advancements in Bioretention medias and functions continue through research, primarily for the purposes of extending the bioretention systems' life expectancy. With the implementation of under-drain systems of bioretention systems, the life expectancy of the system has been increased without losing the high quality of water treatment. The success of evapotranspiration systems is associated with the aesthetics and the creation of open channels and streams, restoring ecosystems in urban areas where they have been lost for decades, if not for centuries. Natural underground storage offers a similar opportunity to re-establish lost or disturbed water tables or perched aquifers, and can occur under streets and sidewalks, which are common within the urban environment. Since streets and sidewalks are in the public domain, this can offer local governments the opportunity to employ this green stormwater BMP without impacting private lands.
However, the current green stormwater Best Management Practices may be limited by cost, the land requirement, and contaminated soils. Costs associated with the acquisition of land, construction, and material can be challenges for the implementation of these BMP's in urban areas. Many of these BMP's are difficult to implement in deep urban areas where minimal land is available and contaminated materials from the industrial age have created more complex environments. Specifically, bioretention and underground storage are difficult to apply in urban environments with contaminated soils, as they can carry the contaminants into adjacent streams and waterways. As with the other green stormwater BMPS mentioned, evapotranspiration creates open channels, requiring specific topography and open space. While successful once they are implemented, the costs, land requirements, and presence of contaminants prevent many communities from using these BMP's.
Therefore, there is a need for an improved apparatus for treating stormwater or wastewater runoff that can at least contribute to the reduction of CSO and SSO activity in a more cost effective manner through ease of implementation.